Under the Categories panel on the bottom left there exists some predefined categories (Unread, Starred, Deleted and Labels). Is it possible to have a category called Read which contains all the feed items that have been read or marked read? This would be the opposite of the Unread category.
unfortunately this is currently not possible.
What are you trying to achieve by this?
A workaround might be to create a filter with
condition: Status - is - read
action: Add Star
and use the pre-defined "Show Starred" filter from the news panel.
I was trying to look back at Feed items that I had Read or marked Read. I already use the Starred feature to highlight certain articles, so that would not work for me. It just seemed to me that the logical opposite of Unread items would be Read items and it would be nice if there was a Category for them.